Jan. 13WASHINGTON  As more large dairies enter the robust organic milk business, the U.S. Department of Agriculture plans to clarify what it means to be an organic dairy cow.

In a letter earlier this week, USDA officials asked a federal advisory panel, the National Organic Standards Board, to produce a "guidance document" elaborating on a provision in the federal code that requires organic cows to have "access to pasture."

The request came Monday, the same day that the Tribune published a story about a rift among organic industry leaders over the pasture requirement.

One group, led by George Siemon, chief executive of the Organic Valley dairy in LaFarge, Wis., argues that organic cows should spend their days munching grass in open pastures, a formula rooted in his belief that a key mission of the organic industry is supporting family farms.

The other side, led by Mark Retzloff, a co-founder of Horizon Organic Dairy in Longmont, Colo., contends that there is a place in the organic business for large-scale dairies where cows are fed organic grains in outdoor pens.

The large-scale dairies not only can make milk cheaper, lowering the costs for consumers, but also increase the amount of cropland that converts to organic to feed all the cows, said Retzloff, who is now chief organic officer of the 5,300-cow Aurora Organic Dairy in Colorado.

Richard Mathews, associate deputy administrator of the USDA's National Organic Program, requested the guidance document later that day. Mathews could not be reached for comment on the letter.

"We are obviously pleased at the rapid response to our concern that factory dairy farms are playing loose with the organic rules," said Mark Kastel, director of the Cornucopia Institute.

Retzloff described Kastel's complaint as "frivolous and destructive to the entire industry." He said that Aurora Organic Dairy adheres to all federal regulations.

Some cows at the dairy graze on pastureland, namely cows in the late stages of milk production and those that are dry, or aren't producing milk, Retzloff said. Most cows producing milk are housed in outdoor pens.

While the federal rule requires organic dairy cows to have access to pasture, it provides exemptions for bad weather, animal health and undefined "stages of production" for the animal.

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